1. Field of the Invention
The present invention relates to a display apparatus and a control method thereof, and more particularly, to a display apparatus and a control method thereof preventing a screen modulation when identical display data are displayed on a screen over a long period of time.
2. Description of the Related Art
A display apparatus, for example, a display apparatus used in an airport or a bank, often displays identical data carrying specific character messages over a long period of time at a stationary position on the display apparatus. In such case, a screen modulation occurs due to a physical variation of a displaying component of the display apparatus. For example, if an identical image is displayed on an LCD (liquid crystal display) over the long period of the time, an array of liquid crystals solidifies, making it difficult to display another image.
To solve such a problem, a method of adding dummy data at each specific frame using a pixel shift, a screen saver, or a scaler was adopted. But, the pixel shift and the screen saver cannot provide a user with information displayed on the screen. Particularly, the pixel shift cannot solve a screen modulation problem when an identical color is displayed within a fixed pixel shift range. Also, the screen may blink when the dummy data are added at each specific frame.